BED-LLM: Intelligent Information Gathering with LLMs and Bayesian Experimental Design
Abstract
We propose a general-purpose approach for improving the ability of large language models (LLMs) to intelligently and adaptively gather information from a user or other external source using the framework of sequential Bayesian experimental design (BED). This enables LLMs to act as effective multi-turn conversational agents and interactively interface with external environments. Our approach, which we call BED-LLM (Bayesian experimental design with large language models), is based on iteratively choosing questions or queries that maximize the expected information gain (EIG) with respect to a variable of interest given the responses gathered previously. We show how this EIG can be formulated (and then estimated) in a principled way using a probabilistic model derived from the LLM's predictive distributions and provide detailed insights into key decisions in its construction and updating procedure. We find that BED-LLM achieves substantial gains in performance across a wide range of tests based on the 20 Questions game and using the LLM to actively infer user preferences, compared to purely prompting-based design generation and other adaptive design strategies.
Cite
@article{arxiv.2508.21184,
title = {BED-LLM: Intelligent Information Gathering with LLMs and Bayesian Experimental Design},
author = {Deepro Choudhury and Sinead Williamson and Adam Goliński and Ning Miao and Freddie Bickford Smith and Michael Kirchhof and Yizhe Zhang and Tom Rainforth},
journal= {arXiv preprint arXiv:2508.21184},
year = {2026}
}
Comments
Published at the International Conference on Learning Representations 2026